Atomic scale friction between the moscovite mica cleavage plane and a tungsten tip

An atomic force microscope using optical lever detection has been used to study the friction between muscovite mica and a tungsten tip. The frictional force is shown to vary laterally with the periodicity of the hexagonal layer of SiO4 units that forms the cleavage plane of mica. The frictional force varies linearly with normal force, giving a coefficient of friction of 0.09. © 1988 American Institute of Physics.